Log4Shell

The Log4Shell exploiter exploits CVE-2021-44228 external link .

Description

Some versions of Apache Log4j, a Java logging framework, have a logging feature called “Message Lookup Substitution” enabled by default. This allows replacing certain special strings by dynamically-generated strings at the time of logging. If log messages or log message parameters can be controlled by an attacker, arbitrary code can be executed. The Log4Shell exploiter takes advantage of this vulnerability to propagate to a victim machine.

You can learn more about this vulnerability and potential mitigations here external link .

Services exploited

The Infection Monkey will attempt to exploit the Log4Shell vulnerability in the following services:

  • Apache Solr
  • Apache Tomcat
  • Logstash

Note: Even if none of these services are running in your environment, running the Log4Shell exploiter can be a good way to test your IDS/IPS or EDR solutions. These solutions should detect that the Infection Monkey is attempting to exploit the Log4Shell vulnerability and raise an appropriate alert.